- At-risk infants will be infants who present with confirmed meconium and/or urine toxicology report (documented in medical chart review) for opioids (e.g., methadone, buprenorphine/subutex, oxycodone, heroin); may also have prenatal exposure to benzodiazepines, barbiturates, amphetamines, cannabinoids, alcohol, nicotine and/or caffeine.